The IP address has dual functions in TCP/IP (Transmission Control Protocol/Internet Protocol) widely used in the existing Internet, i.e., the IP address serves not only as the location identifier of the host network interface of the communication terminal of the network layer in the network topology, but also as the access identifier of the host network interface of the transmission layer. The case of host mobility was not taken into consideration when the TCP/IP protocol was initially designed. However, as host mobility becomes more and more popular, the defect of semantics overload of this kind of IP address becomes more and more apparent. When the IP address of a host changes, not only the route, but also the access identifier of the communication terminal host changes, which will result in bigger and bigger load of the route, and the change of the host identifier will cause interruption of application and connection. The access identifier and location separation problem is proposed to aim to solve the problems of semantics overload of the IP address, severe load of the route and so on, separate the dual functions of the IP address, realize support for problems including mobility, multi-homeness, dynamic redistribution of IP addresses, reduction of route load, and inter-visit between different network areas in the next generation of internet.
In the prior art, the implementing method based on a network router is one of the solutions about access identifier and location separation.
In the prior art, the format of the host identifier is the IPV4 address, and the access identifier compatible with the upper-layer application can be only in IPV4 format. As the popularity and development of IP application, the IPV4 address space cannot meet the requirement for the number by the service applications any more. In the prior art, some new methods for implementing the access identifier, for example, IPV6 address, user identity recognition in HIP (Host Identity Protocol), are defined. These methods are implemented by increasing the bit length of the identity recognition, and only consider how to expand the number of name and address spaces. When the specific functions, like how to be compatible with the existing IPV4 and IPV6 terminals, how to be compatible with the upper-layer application, transplant of IPV4 and IPV6 service application, are related, all of these need to be implemented by way of upgrading HOST software or modifying the service application programs. The prior art realizes intercommunication with the IPV4 terminal by way of supporting dual stack in the network or the terminal, and does not consider compatibility processing functions in access of the IPV4 terminal, transplant of IPV4 services and other aspects.